The present invention relates to improved methods and devices for tissue regeneration especially bone augmentation.
Treatment of edentulous patients with osseointegrated fixtures made of titanium is a well-known procedure in the art. The procedure includes installing a fixture in the alveolar bone of an at least partially edentulous jaw. Usually several months are required for proper healing after fixture installation.
After healing, an abutment is installed on the upper portion of the fixture. After several weeks, an artificial tooth may be mounted on the abutment and the procedure is complete.
Installation of implants requires sufficient alveolar bone, generally about 10 mm height and 6 mm width.
When a tooth is removed, the alveolar bone is gradually resorbed because of the absence of stimulus of ossification-inducing pressure from the teeth. As the resorption process advances, the size of the bone gets reduced, i.e. the bone on which the dental roots are positioned—the alveolar ridge start shrinking.
The absence of just one tooth can cause modifications throughout the dental arch and even prompt a possible softening (loss of insertion) which may cause the loss of other teeth. The absence of several teeth aggravates the problem. Bone loss may finally modify the patient's appearance and, depending on the loss, may make him incapable of receiving bridges, implants or even dentures.
It is then necessary to carry out several surgical operations to reconstruct the alveolar ridge of the maxilla or mandible.
Although these methods of surgical reconstruction have been successfully performed, this type of operation has had drawbacks. Certain methods have involved opening the periosteal tissue (which is the tissue surrounding the bone and is easily detached from the bone) along the entire length of the atrophic alveolar ridge and then placing a bone graft material and a membrane on top of the graft and then suturing the delicate periosteal tissue back together to cover the membrane. The role of the membrane is to maintain the bone graft in its place and to prevent the mucoepithelium from growing into the graft and interfering with the process of bone regeneration. This surgical operation called guided bone regeneration has had drawbacks resulting from the lack of enough soft tissue to cover the enlarged bone.
In order to overcome some of these drawbacks, another small surgical procedure is done before the performance of the procedures mentioned above. In this procedure an expandable device is placed beneath the periosteum through a small incision. This device made of silicon is gradually filled with a liquid through a cannula. While this expandable device expands tension is transferred to the periosteum leading to enlargement of the periosteum. When the periosteum reached the desired dimension the expandable device is taken out and a bone graft is placed as described above, but now there is no need to stretch the mucoperiosteal tissue therefore reducing the complications.
This procedure has two significant drawbacks:                1. Two surgical procedures are needed. A small procedure for insertion of the expandable device and a big procedure for placing the bone graft and the membrane.        2. All the hazards of a relative big operation in the mouth.        
Another method to regenerate bone is distraction osteogenesis, which is a process whereby bone is stretched to increase bone volume. According to distraction osteogenesis processes, at least one portion of a bone is at least partially separated from the bone. The position of the portion is gradually altered with respect to the bone. Time is then provided for new bone to fill in the space between the portion and the overall bone.
When distraction osteogenesis is used in dentistry dental applications, a portion of a patient's jawbone will be at least partially severed from the overall jawbone. The jawbone segment may then be gradually separated from the rest of the jawbone. New bone then fills in the space between the segment and the jawbone. By increasing the volume of bone in the jawbone, additional area can be provided to anchor or at least more securely anchor dental implants. Distraction osteogenesis can also be used in dental applications simply to strengthen a location on the jawbone to increase the bone volume at that location even if implants are not to be secured in the jawbone at that location.
These techniques of distraction osteogenesis has some disadvantages:    1) It is difficult technically to the surgeon.    2) It is traumatic to the patient.    3) This procedure can be done if the height of the ridge is at least 6 mm    4) This technique is not using the new materials available today that enhance bone regeneration.
The present invention is unique because these methods and devices allow distraction osteogenesis without cutting a segment of the bone therefore the procedure is simple minimal invasive and not traumatic. In the present invention only the periosteal tissue is separated from the bone. In another embodiment of the invention materials that enhance bone regeneration can be added to the distraction gap.